When it comes to continuity, comic books have a reputation for constantly altering what has happened before. Through the use of retroactive continuity (what we like to call retcons), storylines are changed, characters are brought back from the death, and events are widely different than we remember them being. When you’re telling one continuous story over several decades, and that story is written and drawn by dozens of creators, stories become conflicted and lines are blurred. Sometimes they work to enhance an old story and sometimes they can fix a mistake. It’s only by suspending our disbelief and accepting that these kind of things can happen in this world that comic book storylines can work like this.

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We can usually avoid these kinds of continuity snafus when it comes to the comic book movies, but over the years we have seen our fair share of odd decisions that change everything that came before. When it comes to complicated and confusing timelines, no one does it better than Fox’s X-Men movie universe. Even the Marvel Cinematic Universe has its fair share of continuity mixups and changes. In order to keep track of all these screw ups, here are 15 times superhero movies ruined their own continuity.

15 THE RELATIONSHIP OF RAVEN AND XAVIER

Mystique with Magneto and Xavier

In the original X-Men movie trilogy, Mystique was Magneto’s top lieutenant in his fight for a mutant revolution. Everyone knew how dangerous she was, but no one knew her quite like Magneto did. That’s until X-Men: First Class turned out to be a prequel, and the film made quite a few changes to continuity. It was revealed that Raven and Charles Xavier were basically brother and sister.

Now, when you look back on the original movies, you’ll notice that Mystique and Xavier really don’t have any kind of meaningful interaction. While it’s clear their lives were heading in different directions, it’s hard to imagine that they would have absolutely no relationship in the end. It’s clear that some decisions were made without anyone thinking long-term about the X-Men film series.

14 THERE IS MORE THAN ONE DEADPOOL

The X-Men movie universe has two Deadpools in it, and they are both played by Ryan Reynolds. In X-Men Origins: Wolverine, Wade Wilson shows up and is ultimately transformed into Weapon XI, a deadly mutant monster. The depiction of the character was so reviled that Fox set out to create a Deadpool movie with Reynolds that actually portrayed the character as audiences know him.

While Deadpool was great, it can’t be ignored that both films still take place in the same universe. Considering that Origins was a prequel movie, it also conflicts with the character’s origin in his own film. At this point it may be easier to just pretend that the 2009 film never actually happened thanks to how much it contradicts with several other movies.

13 WOLVERINE’S AMAZING HEALING ABILITIES

The 2013 film The Wolverine takes place after the events of X-Men: The Last Stand and sees Logan living in Japan. At the end of this movie, Wolverine loses his adamantium claws but grows back his natural bone claws. While it is established that he can regenerate from basically any injury, it’s not very likely he has the ability to regrow his metal claws.

Despite this fact, he appears in the scenes set in the future from Days of Future Past with metal claws again. When his mind is sent back in time to the 1960s, he’s clearly shocked that he had bone claws and not his familiar adamantium ones. Maybe Magneto gave him metal claws again, but you would think his bone claws wouldn’t surprise him that much.

12 BATMAN KNOWS WONDER WOMAN

Wonder woman in Batman v Superman

In Batman v Superman: Dawn of Justice, Batman makes an offhanded joke about the appearance of Wonder Woman at the climax of the film. Superman asks the Dark Knight if she came with him, but he responds that he thought she came with the Man of Steel. It’s played up for laughs, but it’s not funny because Batman knows exactly who she is.

Bruce Wayne has met Diana Prince before, he’s seen the picture of her as Wonder Woman during World War I, and he knows that she’s a metahuman, so it makes no sense for him to say something like this. It’s clear that the studio just wanted to add some more lighthearted moments to the film after fan reaction seemed to hate the dark nature of the DCEU. Still, it makes no sense.

11 EMMA FROST IS BENJAMIN BUTTON

The only way to explain Emma Frost’s appearances in the X-Men movies is that she clearly ages in reverse. We first see Emma in X-Men Origins: Wolverine, where she is one of the many mutant children who have been captured by William Stryker. Charles Xavier arrives, saves them, and we can assume starts his school with their help.

The only problem is that Emma Frost also appears in X-Men: First Class as a member of the Hellfire Club, which takes place in the 1960s, well before her first appearance. She is also much older in this film, so it’s hard to rectify how she could fit into both films unless she actually ages backwards. Maybe one day we will find out that she’s actually a secret time traveler.

10 A TALE OF TWO INFINITY GAUNTLETS

It’s clear that early in Phase One of the MCU, Marvel Studios had no idea what it was doing yet. No reveal makes this more apparent than the scene depicting Odin’s treasure room during the events of Thor. The Vault contains powerful artifacts, and one of them shouldn’t be there. In a blink-and-you’ll-miss-it shot, you can clearly see a right-handed Infinity Gauntlet on display in the treasure room.

Thanos is later seen wearing the Gauntlet at the end of Avengers: Age of Ultron. This one is left-handed, and while Marvel has said there are two in this universe, that revelation seems inconsequential. Only the Gems hold power, and there aren’t enough of those to fill two gloves. We know the Asgardians only ever had one of the stones, so this is clearly a goof they are trying to cover for.

9 TONY STARK’S “TEAM”

Tony Stark shows up in the post-credit scene in 2008's The Incredible Hulk

At the end of The Incredible Hulk, Tony Stark shows up and tells General Ross that they are putting together a team. What team would that be, and who exactly do they want on this team? We have no idea. It’s clear that Marvel just wanted Robert Downey Jr. back on the screen as quickly as possible.

Nick Fury had already attempted to recruit Iron Man into the Avengers Initiative, so suddenly he’s a spokesman for S.H.I.E.L.D.? The events from Iron Man 2 were all about Tony Stark not being Avengers material. The Avengers are eventually assembled in a different way, so Marvel tried to save face by explaining it away in The Consultant short film. Apparently it was a trick to convince Ross to keep Blonsky imprisoned... or something.

8 TIME TRAVEL FROM DAYS OF FUTURE PAST

Days of Future Past Wolverine

If we’re talking about movies that ruin their own continuity, we have to bring up X-Men: Days of Future Past. First Class seemed like a nice reboot of the X-Men films, until Days of Future Past attempted to merge elements of the two continuities, and the whole thing turned into a mess. Basically any time you introduce time travel, it screws things up if you don’t go out of your way to explain everything.

While the movies have done a poor job showing us what is and isn’t in continuity, it can be assumed that the return of Cyclops and Jean Grey has undone the events of X-Men: The Last Stand. What about the other films, though? There’s actually a map of the timeline out there that tries to rectify everything.

7 THE MANY LIVES OF WARREN WORTHINGTON III

In X-Men: The Last Stand, Warren Worthington III is a rich kid who struggles to follow in his father’s footsteps while he transforms into a mutant. By the end of the film, we see his complete story arc come to a close as he embraces who he is and accepts his place among the X-Men. It’s pretty clear he’s never met any of them before, but in X-Men: Apocalypse things are very different.

The film is set in the ‘80s, well before the start of the original trilogy, but instead of being a rich kid, Angel is now a mutant street fighter whose powers are already established. He is recruited by En Sabah Nur and takes on the X-Men before being ultimately defeated. His inclusion in the movie defies continuity in a number of ways.

6 THE TRUTH ABOUT LOKI’S SCEPTER

Thanos gives Loki more power in exchange for retrieving the Tesseract from Earth, which sets the events of The Avengers in motion. The Asgardian shows up on Earth with a new weapon in the form of a scepter and uses it to control the minds of his victims. It all makes sense until you realize that both items actually contain Infinity Stones.

At the end of Avengers: Age of Ultron, we see Thanos with the Infinity Gauntlet, showing that his motive is to collect the Infinity Stones. It then doesn’t make sense that he would give away the Mind Stone inside the scepter just so he can get his hands on the stone in the Tesseract. Either Thanos is really dumb, or Marvel hadn't thought that far in advance yet.

5 HARLEY QUINN’S TIMELINE MAKES NO SENSE

We know that the Joker was responsible for the death of Robin based on the graffitied uniform in the Batcave during Batman v Superman: Dawn of Justice. Suicide Squad adds another element to the killing by outright stating that Harley Quinn is an accomplice to the murder, which is all well and good, but the timeline doesn’t make sense.

According to David Ayer’s own explanation, once he heard that his movie was being made fun of, the Joker murdered Robin, so Batman bashed out his teeth and threw him in Arkham Asylum. This would have been when he met Harley, got the grill, and tattooed his head. However, if Harley was already with him before Arkham, he would have had normal teeth in their scenes together. This is what happens when you get lost in your own headcanon.

4 HOW IS CHARLES XAVIER WALKING

One of the biggest mysteries over in Fox’s X-Men universe is how Charles Xavier always seems to be able to walk when he shouldn’t be. In fact, it’s been an ongoing thing for him in the comics, too. We know that the character, as portrayed by Patrick Stewart, is paralyzed from the waist down, but in X-Men: The Last Stand, when Xavier and Magneto recruit Jean Grey in 1985, he can walk. He can also walk in X-Men Origins: Wolverine.

However, this directly conflicts with what we see in X-Men: First Class, where a much younger Xavier — who has hair by the way — is first crippled at the end of the film set in the ‘60s. It doesn’t make much sense that he would then be able to walk later in his life, only to be paralyzed during the events of the original trilogy.

3 CAPTAIN AMERICA’S DESTRUCTION

We all know by now that Captain America was thought dead, only to reappear in the modern world frozen in ice. We saw this play out at the end of Captain America: The First Avenger and the beginning of The Avengers. The problem was that this directly contradicted his appearance in 2008’s The Incredible Hulk, and you never knew he was there.

In the original opening to the movie, Bruce Banner travels to the arctic to commit suicide, only to transform into the Hulk and completely destroy a large formation of ice. In the middle of the destruction, we catch a brief glimpse of Cap’s body frozen in ice. This scene was included in the extended cut of the film, but it directly conflicts with his body still being stuck inside that giant plane.

2 WHAT WAS THE POINT OF THE TEN RINGS

The terrorist group that kidnaps Tony Stark in the desert is called the Ten Rings. It’s a subtle reference to The Mandarin, a villain that director Jon Favreau was building toward in his original plan for a trilogy. The Ten Rings continued to appear across all three movies, but when the Mandarin was finally revealed, it was all a hoax.

The new creative team behind Iron Man 3 thought this would be a cool revelation, but it doesn’t make sense. If the Mandarin was an actor created by Aldrich Killian, then the Ten Rings weren’t real either. So then what exactly was the group’s motivation before this reveal? Killian is now indirectly responsible for creating Iron Man in the first place. Marvel released a short film as an attempt to rectify this, but it’s basically been ignored since.

1 SONY RUINS SPIDER-MAN

Sandman kills Uncle Ben in flashback from Spider-Man 3

In Spider-Man, we see the iconic origin story of Peter Parker’s superhero career play out much in the same way it happened in the comics. Peter has a chance to stop a criminal, chooses not to, and the guy ends up killing his Uncle Ben. It’s truly a tragic tale of consequence and responsibility, which shows us that every action (or inaction) has a reaction.

In Spider-Man 3, Sony spits all over the story by altering the way that Uncle Ben died, which doesn’t really line up with the original film. Not only did the film throw Sandman into the origin of Spider-Man, they turned the death of Uncle Ben into an accident? Then Spider-Man goes on a rampage to get revenge on Sandman for, what, tapping his friend on the shoulder at the wrong time? It was bad.

Do you know of other incidents where superhero movies ruin their own continuity? Let us know in the comments.